Bulb Placement

Use the wall clues to place bulbs and illuminate every white cell.

Choose a tool, then tap a cell. Repeat to erase a mark.

Use arrow keys to move and Enter to act. Scroll the enlarged board to reach every cell.

How to play

Place bulbs on white cells to illuminate every white cell. Light travels along rows and columns until a wall. No bulb may shine on another bulb. A wall number counts bulbs in its orthogonally adjacent cells. Use × for cells that cannot hold bulbs.

Learn more

Combine wall counts with lines of sight. It also helps to work backwards: which positions could light this cell?